#include <iostream>
#define  maxsize 1000000000000
int dp[maxsize];
using namespace std;
//动态规划 fibonacci
int fibonacci(int n)
{
    if(n==1||n==2)
        return 1;
    else if(dp[n]!=0)
    {
        return dp[n];
    } else
    {
        dp[n]=fibonacci(n-1)+fibonacci(n-2);
        return dp[n];
    }

}
int main() {

   memset(dp,0,10000);

   cout<<fibonacci(70);
    return 0;
}
